What happens if there is a no-deal Brexit?

The UK would sever all ties with the EU with immediate effect, with no transition period – and, therefore, no talks on a tailor-made trade deal between the UK and the EU.

The UK would trade with the EU under World Trade Organisation rules, in the same way that it does with many non-EU countries.

Who is against a no-deal Brexit and why?

The government fears it would cause significant disruption to businesses in the short-term, with lengthy tailbacks of lorries at the channel ports, as drivers face new checks on their cargos.

Food retailers have warned of shortages of fresh produce and the NHS is stockpiling medicines, in case supplies from EU countries are interrupted.

Government ministers and multinational companies with factories in the UK have also warned about the long-term impact on the British economy.

Most MPs are thought to be against a no-deal Brexit for these reasons.

Who is in favour of a no-deal Brexit and why?

Many who campaigned for Brexit in the 2016 referendum believe the no-deal warnings have been exaggerated and that Britain will not only survive, but thrive, if it is allowed to make a totally clean break from the EU and what they see as its burdensome regulations.

They fear the UK will never be allowed to make trade deals with other countries if it ends up trapped in a customs union with the EU.

And the country would also save on the £39bn “divorce bill” it is set to pay to the EU under the terms of Mrs May’s agreement.

Could Brexit be delayed?

The 29 March exit date could slip if MPs vote to ask for an extension from the European Union, something that might happen on Thursday.

The EU may decide not to grant an extension unless the UK has a reason for it, such as deciding to hold another EU referendum, with the option of staying in the EU on the ballot paper.

And the UK government could cancel Brexit altogether if it wanted to. But as things currently stand Brexit is definitely happening.

What about other Brexit deals?

Having been comprehensively rejected twice by MPs, many think the prime minister’s deal is now dead.

So MPs are proposing different ideas for deals. Labour wants the UK to be in a customs union with the EU, and some Labour and Tory MPs want an even closer relationship, like the one Norway has with the EU.

There are no votes today on these options.

MPs will vote, however, on proposals from a group of Conservative MPs for a “managed no-deal”, which would see the transition period extended by a year until December 2021 to allow more time to agree a new trading relationship.

The backstop would be replaced by a free trade agreement with technological solutions to avoid customs checks at the Irish border.

The EU has said this option is not possible and the deal it has reached with the PM is the only one that is on offer.